Portable electronic devices are becoming increasingly popular. Examples of portable electronic devices include laptop computers, personal digital assistants (PDAs), mobile telephones, media players, and hybrid devices that provide a combination of the functionalities of the above devices.
To satisfy consumer demand for small and lightweight portable electronic devices, manufacturers are continually striving to reduce the size of the devices while providing enhanced functionality. When electronic components are tightly packaged in a small device, heat dissipation becomes an important issue. As most consumer electronics cannot function properly at a high temperature for an extended period of time, manufacturers often place temperature sensors, such as thermistors, to monitor the internal temperature of the electronic devices. These temperature sensors allow out of range temperature scenarios to be recognized, so that mitigation actions can be taken before system failure.
Conventionally, temperature sensors in a device are calibrated to ensure their accuracy, by heating up the device to a known temperature. The output of the temperature sensors is then compared with an expected temperature to determine an error in the sensor output. This error is then stored in the device for later use. Thereafter, the device, while being used “in the field”, then automatically compensates the readings from its sensors using the stored error values. However, the conventional calibration process requires heating up the motherboard of a device in an oven, which is a complex process in terms of time and resources. Further, the conventional calibration process cannot be performed in the field, i.e. after the devices have been packaged and shipped by its manufacturer for resale.